Just when you thought you'd memorized the periodic table of the elements, along comes a new one. The atomic weight is 115, and ununpentium is its temporary name (it just means 115).

The heaviest element in nature is uranium, which has 92 protons. But heavier elements-which have more protons in their nucleus-can be created through nuclear fusion. (Related: Learn how to make an element.)

The man-made 115 was first created by Russian scientists in Dubna about ten years ago. This week, chemists at Lund University in Sweden announced that they had replicated the Russian study at the GSI Helmholtz Center for Heavy Ion Research in Germany.

Element 115 will join its neighbors 114 and 116-flerovium and livermorium, respectively-on the periodic table just as soon as a committee from the International Union of Pure and Applied Chemistry (IUPAC) decides on an official name for 115.

Don't think for a minute they will name it by internet poll. Chemistry professor Paul Hooker talked to National Geographic News about the process for discovering and confirming this new element. Link